It is also stated on page 72 that the longer branch must be outside the vessel. This is not necessary, for the instrument will work with the shorter branch outside, provided that the extremity of that branch be below the surface of the fluid. 8. To the Thermometers it might be well to add that which is called De Lisle's. This is much used in Russian scientific operations. In it the boiling point is marked 0o, and the freezing point 150°, 9. It should be carefully observed that the freezing point of a Thermometer is found by placing the instrument not in freezing water, but in melting ice. 6. The area of a circle whose radius is r is π2, and tak ing as an approximate value of π, the answer is 5587cwt 13. Since the external pressure on the cork increases with the depth, while the internal pressure is constant, the cork will be forced in when the former exceeds the latter. 18. If d1, de, d, be the measures of the densities of the fluids, and d be the measure of the density of the mixture, d=3d-d1-d2. 19. 8.241... 20. 8i. 21. 18:41. 22. 1.61... 23. 3.13. 24. 86... oz. 25. The volumes are as 57: 1, the weights as 4446: 97. 26. Because the specific gravity of salt water is greater than that of fresh water. downwards; 3: 4 when vertex is upwards. 35. 75. 36. 2 inches. 39. 4 lbs. 42. w1(w2-w) : w2 (w1—w). wood be lighter than water. 31. 52. 33. 14 when vertex is 34. 16 lbs. 26 37. 9. 38. inch. 135 43. 44. 32. Increased, if the 45. 9. 64. 920 grains. 65. 11 or 10272 nearly. 66. 54. 69. 24.7 cub. in. EXAMPLES V. (page 60.) 1. Density = (19) times original density. original pressure. 3. 91. 4. No. because the pressure varies with the depth alone; so that if the section varied there would still be equal vertical increments of space for equal increments of pressure. 931 5. 53 lbs. 6. 113 inches. 7. The mercury would fall to the level of the surface in the cup. 8. 14.625 lbs. 9. 10 feet. 10. No because a volume of mercury equal to that displaced by the iron will descend and allow the iron to take its place without disturbing the general upper surface. 11. Sink: see answer to (16). 12. The mercury would descend a little. 13. 238 square inches. 14. 0109 of original volume. 15. 1 ft. 597 in. 16. When the floating body is partially immersed, both air and water are displaced: but the absolute weight of floating body weight of displaced fluids, which must therefore be constant: therefore when the barometer rises, there must be a less water displacement, i.e. the body rises: while any decrease in the atmospheric pressure (when the barometer falls) will necessitate an increased water displacement, and therefore the body then sinks a little. 17. 12. 20. 288 inches. 22. 2613 inches. 23. 5 feet. 21. 1080 lbs. 24. 6 1. 25. The air will be compressed inside, and so displace less water: and since it floated originally, it will now sink, because the weight of displaced fluid is now less than the weight of the body. 26. 5 times original pressure. 85 28. 50 oz. 27. 32 ft. 29. 4776 oz. 32. The space between zero point and any graduation ought to be less than the space indicated by the number placed against that graduation in 33. 18 1505 lbs. nearly. the ratio of 17: 18. 9* 34. of 36.9 inches. EXAMPLES VI. (page 75.) 1. It will increase the time of filling the receiver, since the only effective work would be done by the descending piston, after passing the hole. It will fill the tank in 3 times the original time. 2. 277 lbs. 3. (a) If the hole be below the level of short end, no effect. (B) If above this level but still in the long branch, all the fluid in this branch below the hole will descend, and all above in the same branch will ascend, causing the remainder of the fluid to flow through the short branch, till the siphon is emptied. (y) If in the short branch, all the fluid below the hole is this branch will descend; all above in the same branch will ascend and flow through the long branch, emptying the siphon. (8) If at the top of the siphon, the fluid will descend in each branch and empty the siphon. 4. 32 ft. 9:53 in. or 32.79416 feet. 5. The fluid would descend in each branch and the siphon be emptied. 6. At the bottom. than the surface in harbour. 7. No: because the hold is lower 8. 33 ft. 11.1 in. 9. If the air be removed from the siphon, the fluids would first ascend in each branch and afterwards flow as usual. 10. The water would rise in the inverted tube as high as the top of the inserted tube and afterwards flow out of it. 11. First, the water would soon cease to flow. Secondly, it would rise in each branch, and afterwards flow. 12. (a) The water will flow into the lower vessel. (8) The water will descend in each branch till it stands at 34 feet above each surface. (y) The same as (a). 13. Each branch 2 feet. |